From 5d6d1ddd27301dc85b13b794262c8bcececf88f1 Mon Sep 17 00:00:00 2001 From: "Luis R. Rodriguez" Date: Sat, 10 Mar 2018 06:14:50 -0800 Subject: firmware: move firmware loader into its own directory This will make it much easier to manage as we manage to keep trimming componnents down into their own files to more easily manage and maintain this codebase. Suggested-by: Kees Cook Signed-off-by: Luis R. Rodriguez Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_loader/fallback.c | 661 ++++++++++++++++++++++++++++++++ 1 file changed, 661 insertions(+) create mode 100644 drivers/base/firmware_loader/fallback.c (limited to 'drivers/base/firmware_loader/fallback.c') diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c new file mode 100644 index 000000000000..9b65837256d6 --- /dev/null +++ b/drivers/base/firmware_loader/fallback.c @@ -0,0 +1,661 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include +#include +#include +#include +#include + +#include "fallback.h" +#include "firmware.h" + +/* + * firmware fallback mechanism + */ + +extern struct firmware_fallback_config fw_fallback_config; + +/* These getters are vetted to use int properly */ +static inline int __firmware_loading_timeout(void) +{ + return fw_fallback_config.loading_timeout; +} + +/* These setters are vetted to use int properly */ +static void __fw_fallback_set_timeout(int timeout) +{ + fw_fallback_config.loading_timeout = timeout; +} + +/* + * use small loading timeout for caching devices' firmware because all these + * firmware images have been loaded successfully at lease once, also system is + * ready for completing firmware loading now. The maximum size of firmware in + * current distributions is about 2M bytes, so 10 secs should be enough. + */ +void fw_fallback_set_cache_timeout(void) +{ + fw_fallback_config.old_timeout = __firmware_loading_timeout(); + __fw_fallback_set_timeout(10); +} + +/* Restores the timeout to the value last configured during normal operation */ +void fw_fallback_set_default_timeout(void) +{ + __fw_fallback_set_timeout(fw_fallback_config.old_timeout); +} + +static long firmware_loading_timeout(void) +{ + return __firmware_loading_timeout() > 0 ? + __firmware_loading_timeout() * HZ : MAX_JIFFY_OFFSET; +} + +static inline bool fw_sysfs_done(struct fw_priv *fw_priv) +{ + return __fw_state_check(fw_priv, FW_STATUS_DONE); +} + +static inline bool fw_sysfs_loading(struct fw_priv *fw_priv) +{ + return __fw_state_check(fw_priv, FW_STATUS_LOADING); +} + +static inline int fw_sysfs_wait_timeout(struct fw_priv *fw_priv, long timeout) +{ + return __fw_state_wait_common(fw_priv, timeout); +} + +struct fw_sysfs { + bool nowait; + struct device dev; + struct fw_priv *fw_priv; + struct firmware *fw; +}; + +static struct fw_sysfs *to_fw_sysfs(struct device *dev) +{ + return container_of(dev, struct fw_sysfs, dev); +} + +static void __fw_load_abort(struct fw_priv *fw_priv) +{ + /* + * There is a small window in which user can write to 'loading' + * between loading done and disappearance of 'loading' + */ + if (fw_sysfs_done(fw_priv)) + return; + + list_del_init(&fw_priv->pending_list); + fw_state_aborted(fw_priv); +} + +static void fw_load_abort(struct fw_sysfs *fw_sysfs) +{ + struct fw_priv *fw_priv = fw_sysfs->fw_priv; + + __fw_load_abort(fw_priv); +} + +static LIST_HEAD(pending_fw_head); + +void kill_pending_fw_fallback_reqs(bool only_kill_custom) +{ + struct fw_priv *fw_priv; + struct fw_priv *next; + + mutex_lock(&fw_lock); + list_for_each_entry_safe(fw_priv, next, &pending_fw_head, + pending_list) { + if (!fw_priv->need_uevent || !only_kill_custom) + __fw_load_abort(fw_priv); + } + mutex_unlock(&fw_lock); +} + +static ssize_t timeout_show(struct class *class, struct class_attribute *attr, + char *buf) +{ + return sprintf(buf, "%d\n", __firmware_loading_timeout()); +} + +/** + * firmware_timeout_store - set number of seconds to wait for firmware + * @class: device class pointer + * @attr: device attribute pointer + * @buf: buffer to scan for timeout value + * @count: number of bytes in @buf + * + * Sets the number of seconds to wait for the firmware. Once + * this expires an error will be returned to the driver and no + * firmware will be provided. + * + * Note: zero means 'wait forever'. + **/ +static ssize_t timeout_store(struct class *class, struct class_attribute *attr, + const char *buf, size_t count) +{ + int tmp_loading_timeout = simple_strtol(buf, NULL, 10); + + if (tmp_loading_timeout < 0) + tmp_loading_timeout = 0; + + __fw_fallback_set_timeout(tmp_loading_timeout); + + return count; +} +static CLASS_ATTR_RW(timeout); + +static struct attribute *firmware_class_attrs[] = { + &class_attr_timeout.attr, + NULL, +}; +ATTRIBUTE_GROUPS(firmware_class); + +static void fw_dev_release(struct device *dev) +{ + struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev); + + kfree(fw_sysfs); +} + +static int do_firmware_uevent(struct fw_sysfs *fw_sysfs, struct kobj_uevent_env *env) +{ + if (add_uevent_var(env, "FIRMWARE=%s", fw_sysfs->fw_priv->fw_name)) + return -ENOMEM; + if (add_uevent_var(env, "TIMEOUT=%i", __firmware_loading_timeout())) + return -ENOMEM; + if (add_uevent_var(env, "ASYNC=%d", fw_sysfs->nowait)) + return -ENOMEM; + + return 0; +} + +static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev); + int err = 0; + + mutex_lock(&fw_lock); + if (fw_sysfs->fw_priv) + err = do_firmware_uevent(fw_sysfs, env); + mutex_unlock(&fw_lock); + return err; +} + +static struct class firmware_class = { + .name = "firmware", + .class_groups = firmware_class_groups, + .dev_uevent = firmware_uevent, + .dev_release = fw_dev_release, +}; + +int register_sysfs_loader(void) +{ + return class_register(&firmware_class); +} + +void unregister_sysfs_loader(void) +{ + class_unregister(&firmware_class); +} + +static ssize_t firmware_loading_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev); + int loading = 0; + + mutex_lock(&fw_lock); + if (fw_sysfs->fw_priv) + loading = fw_sysfs_loading(fw_sysfs->fw_priv); + mutex_unlock(&fw_lock); + + return sprintf(buf, "%d\n", loading); +} + +/* Some architectures don't have PAGE_KERNEL_RO */ +#ifndef PAGE_KERNEL_RO +#define PAGE_KERNEL_RO PAGE_KERNEL +#endif + +/* one pages buffer should be mapped/unmapped only once */ +static int map_fw_priv_pages(struct fw_priv *fw_priv) +{ + if (!fw_priv->is_paged_buf) + return 0; + + vunmap(fw_priv->data); + fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0, + PAGE_KERNEL_RO); + if (!fw_priv->data) + return -ENOMEM; + return 0; +} + +/** + * firmware_loading_store - set value in the 'loading' control file + * @dev: device pointer + * @attr: device attribute pointer + * @buf: buffer to scan for loading control value + * @count: number of bytes in @buf + * + * The relevant values are: + * + * 1: Start a load, discarding any previous partial load. + * 0: Conclude the load and hand the data to the driver code. + * -1: Conclude the load with an error and discard any written data. + **/ +static ssize_t firmware_loading_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev); + struct fw_priv *fw_priv; + ssize_t written = count; + int loading = simple_strtol(buf, NULL, 10); + int i; + + mutex_lock(&fw_lock); + fw_priv = fw_sysfs->fw_priv; + if (fw_state_is_aborted(fw_priv)) + goto out; + + switch (loading) { + case 1: + /* discarding any previous partial load */ + if (!fw_sysfs_done(fw_priv)) { + for (i = 0; i < fw_priv->nr_pages; i++) + __free_page(fw_priv->pages[i]); + vfree(fw_priv->pages); + fw_priv->pages = NULL; + fw_priv->page_array_size = 0; + fw_priv->nr_pages = 0; + fw_state_start(fw_priv); + } + break; + case 0: + if (fw_sysfs_loading(fw_priv)) { + int rc; + + /* + * Several loading requests may be pending on + * one same firmware buf, so let all requests + * see the mapped 'buf->data' once the loading + * is completed. + * */ + rc = map_fw_priv_pages(fw_priv); + if (rc) + dev_err(dev, "%s: map pages failed\n", + __func__); + else + rc = security_kernel_post_read_file(NULL, + fw_priv->data, fw_priv->size, + READING_FIRMWARE); + + /* + * Same logic as fw_load_abort, only the DONE bit + * is ignored and we set ABORT only on failure. + */ + list_del_init(&fw_priv->pending_list); + if (rc) { + fw_state_aborted(fw_priv); + written = rc; + } else { + fw_state_done(fw_priv); + } + break; + } + /* fallthrough */ + default: + dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading); + /* fallthrough */ + case -1: + fw_load_abort(fw_sysfs); + break; + } +out: + mutex_unlock(&fw_lock); + return written; +} + +static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store); + +static void firmware_rw_data(struct fw_priv *fw_priv, char *buffer, + loff_t offset, size_t count, bool read) +{ + if (read) + memcpy(buffer, fw_priv->data + offset, count); + else + memcpy(fw_priv->data + offset, buffer, count); +} + +static void firmware_rw(struct fw_priv *fw_priv, char *buffer, + loff_t offset, size_t count, bool read) +{ + while (count) { + void *page_data; + int page_nr = offset >> PAGE_SHIFT; + int page_ofs = offset & (PAGE_SIZE-1); + int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count); + + page_data = kmap(fw_priv->pages[page_nr]); + + if (read) + memcpy(buffer, page_data + page_ofs, page_cnt); + else + memcpy(page_data + page_ofs, buffer, page_cnt); + + kunmap(fw_priv->pages[page_nr]); + buffer += page_cnt; + offset += page_cnt; + count -= page_cnt; + } +} + +static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buffer, loff_t offset, size_t count) +{ + struct device *dev = kobj_to_dev(kobj); + struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev); + struct fw_priv *fw_priv; + ssize_t ret_count; + + mutex_lock(&fw_lock); + fw_priv = fw_sysfs->fw_priv; + if (!fw_priv || fw_sysfs_done(fw_priv)) { + ret_count = -ENODEV; + goto out; + } + if (offset > fw_priv->size) { + ret_count = 0; + goto out; + } + if (count > fw_priv->size - offset) + count = fw_priv->size - offset; + + ret_count = count; + + if (fw_priv->data) + firmware_rw_data(fw_priv, buffer, offset, count, true); + else + firmware_rw(fw_priv, buffer, offset, count, true); + +out: + mutex_unlock(&fw_lock); + return ret_count; +} + +static int fw_realloc_pages(struct fw_sysfs *fw_sysfs, int min_size) +{ + struct fw_priv *fw_priv= fw_sysfs->fw_priv; + int pages_needed = PAGE_ALIGN(min_size) >> PAGE_SHIFT; + + /* If the array of pages is too small, grow it... */ + if (fw_priv->page_array_size < pages_needed) { + int new_array_size = max(pages_needed, + fw_priv->page_array_size * 2); + struct page **new_pages; + + new_pages = vmalloc(new_array_size * sizeof(void *)); + if (!new_pages) { + fw_load_abort(fw_sysfs); + return -ENOMEM; + } + memcpy(new_pages, fw_priv->pages, + fw_priv->page_array_size * sizeof(void *)); + memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) * + (new_array_size - fw_priv->page_array_size)); + vfree(fw_priv->pages); + fw_priv->pages = new_pages; + fw_priv->page_array_size = new_array_size; + } + + while (fw_priv->nr_pages < pages_needed) { + fw_priv->pages[fw_priv->nr_pages] = + alloc_page(GFP_KERNEL | __GFP_HIGHMEM); + + if (!fw_priv->pages[fw_priv->nr_pages]) { + fw_load_abort(fw_sysfs); + return -ENOMEM; + } + fw_priv->nr_pages++; + } + return 0; +} + +/** + * firmware_data_write - write method for firmware + * @filp: open sysfs file + * @kobj: kobject for the device + * @bin_attr: bin_attr structure + * @buffer: buffer being written + * @offset: buffer offset for write in total data store area + * @count: buffer size + * + * Data written to the 'data' attribute will be later handed to + * the driver as a firmware image. + **/ +static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buffer, loff_t offset, size_t count) +{ + struct device *dev = kobj_to_dev(kobj); + struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev); + struct fw_priv *fw_priv; + ssize_t retval; + + if (!capable(CAP_SYS_RAWIO)) + return -EPERM; + + mutex_lock(&fw_lock); + fw_priv = fw_sysfs->fw_priv; + if (!fw_priv || fw_sysfs_done(fw_priv)) { + retval = -ENODEV; + goto out; + } + + if (fw_priv->data) { + if (offset + count > fw_priv->allocated_size) { + retval = -ENOMEM; + goto out; + } + firmware_rw_data(fw_priv, buffer, offset, count, false); + retval = count; + } else { + retval = fw_realloc_pages(fw_sysfs, offset + count); + if (retval) + goto out; + + retval = count; + firmware_rw(fw_priv, buffer, offset, count, false); + } + + fw_priv->size = max_t(size_t, offset + count, fw_priv->size); +out: + mutex_unlock(&fw_lock); + return retval; +} + +static struct bin_attribute firmware_attr_data = { + .attr = { .name = "data", .mode = 0644 }, + .size = 0, + .read = firmware_data_read, + .write = firmware_data_write, +}; + +static struct attribute *fw_dev_attrs[] = { + &dev_attr_loading.attr, + NULL +}; + +static struct bin_attribute *fw_dev_bin_attrs[] = { + &firmware_attr_data, + NULL +}; + +static const struct attribute_group fw_dev_attr_group = { + .attrs = fw_dev_attrs, + .bin_attrs = fw_dev_bin_attrs, +}; + +static const struct attribute_group *fw_dev_attr_groups[] = { + &fw_dev_attr_group, + NULL +}; + +static struct fw_sysfs * +fw_create_instance(struct firmware *firmware, const char *fw_name, + struct device *device, unsigned int opt_flags) +{ + struct fw_sysfs *fw_sysfs; + struct device *f_dev; + + fw_sysfs = kzalloc(sizeof(*fw_sysfs), GFP_KERNEL); + if (!fw_sysfs) { + fw_sysfs = ERR_PTR(-ENOMEM); + goto exit; + } + + fw_sysfs->nowait = !!(opt_flags & FW_OPT_NOWAIT); + fw_sysfs->fw = firmware; + f_dev = &fw_sysfs->dev; + + device_initialize(f_dev); + dev_set_name(f_dev, "%s", fw_name); + f_dev->parent = device; + f_dev->class = &firmware_class; + f_dev->groups = fw_dev_attr_groups; +exit: + return fw_sysfs; +} + +/* load a firmware via user helper */ +static int _request_firmware_load(struct fw_sysfs *fw_sysfs, + unsigned int opt_flags, long timeout) +{ + int retval = 0; + struct device *f_dev = &fw_sysfs->dev; + struct fw_priv *fw_priv = fw_sysfs->fw_priv; + + /* fall back on userspace loading */ + if (!fw_priv->data) + fw_priv->is_paged_buf = true; + + dev_set_uevent_suppress(f_dev, true); + + retval = device_add(f_dev); + if (retval) { + dev_err(f_dev, "%s: device_register failed\n", __func__); + goto err_put_dev; + } + + mutex_lock(&fw_lock); + list_add(&fw_priv->pending_list, &pending_fw_head); + mutex_unlock(&fw_lock); + + if (opt_flags & FW_OPT_UEVENT) { + fw_priv->need_uevent = true; + dev_set_uevent_suppress(f_dev, false); + dev_dbg(f_dev, "firmware: requesting %s\n", fw_priv->fw_name); + kobject_uevent(&fw_sysfs->dev.kobj, KOBJ_ADD); + } else { + timeout = MAX_JIFFY_OFFSET; + } + + retval = fw_sysfs_wait_timeout(fw_priv, timeout); + if (retval < 0) { + mutex_lock(&fw_lock); + fw_load_abort(fw_sysfs); + mutex_unlock(&fw_lock); + } + + if (fw_state_is_aborted(fw_priv)) { + if (retval == -ERESTARTSYS) + retval = -EINTR; + else + retval = -EAGAIN; + } else if (fw_priv->is_paged_buf && !fw_priv->data) + retval = -ENOMEM; + + device_del(f_dev); +err_put_dev: + put_device(f_dev); + return retval; +} + +static int fw_load_from_user_helper(struct firmware *firmware, + const char *name, struct device *device, + unsigned int opt_flags) +{ + struct fw_sysfs *fw_sysfs; + long timeout; + int ret; + + timeout = firmware_loading_timeout(); + if (opt_flags & FW_OPT_NOWAIT) { + timeout = usermodehelper_read_lock_wait(timeout); + if (!timeout) { + dev_dbg(device, "firmware: %s loading timed out\n", + name); + return -EBUSY; + } + } else { + ret = usermodehelper_read_trylock(); + if (WARN_ON(ret)) { + dev_err(device, "firmware: %s will not be loaded\n", + name); + return ret; + } + } + + fw_sysfs = fw_create_instance(firmware, name, device, opt_flags); + if (IS_ERR(fw_sysfs)) { + ret = PTR_ERR(fw_sysfs); + goto out_unlock; + } + + fw_sysfs->fw_priv = firmware->priv; + ret = _request_firmware_load(fw_sysfs, opt_flags, timeout); + + if (!ret) + ret = assign_fw(firmware, device, opt_flags); + +out_unlock: + usermodehelper_read_unlock(); + + return ret; +} + +static bool fw_force_sysfs_fallback(unsigned int opt_flags) +{ + if (fw_fallback_config.force_sysfs_fallback) + return true; + if (!(opt_flags & FW_OPT_USERHELPER)) + return false; + return true; +} + +static bool fw_run_sysfs_fallback(unsigned int opt_flags) +{ + if ((opt_flags & FW_OPT_NOFALLBACK)) + return false; + + return fw_force_sysfs_fallback(opt_flags); +} + +int fw_sysfs_fallback(struct firmware *fw, const char *name, + struct device *device, + unsigned int opt_flags, + int ret) +{ + if (!fw_run_sysfs_fallback(opt_flags)) + return ret; + + dev_warn(device, "Falling back to user helper\n"); + return fw_load_from_user_helper(fw, name, device, opt_flags); +} -- cgit v1.2.3 From ceb18132248d95b2c68e30c3df78e69175c4452f Mon Sep 17 00:00:00 2001 From: "Luis R. Rodriguez" Date: Sat, 10 Mar 2018 06:14:51 -0800 Subject: firmware: enable run time change of forcing fallback loader Currently one requires to test four kernel configurations to test the firmware API completely: 0) CONFIG_FW_LOADER=y 1) o CONFIG_FW_LOADER=y o CONFIG_FW_LOADER_USER_HELPER=y 2) o CONFIG_FW_LOADER=y o CONFIG_FW_LOADER_USER_HELPER=y o CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y 3) When CONFIG_FW_LOADER=m the built-in stuff is disabled, we have no current tests for this. We can reduce the requirements to three kernel configurations by making fw_config.force_sysfs_fallback a proc knob we flip on off. For kernels that disable CONFIG_IKCONFIG_PROC this can also enable one to inspect if CONFIG_FW_LOADER_USER_HELPER_FALLBACK was enabled at build time by checking the proc value at boot time. Acked-by: Kees Cook Signed-off-by: Luis R. Rodriguez Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_loader/fallback.c | 1 + drivers/base/firmware_loader/fallback.h | 4 +++- drivers/base/firmware_loader/fallback_table.c | 17 +++++++++++++++++ kernel/sysctl.c | 11 +++++++++++ 4 files changed, 32 insertions(+), 1 deletion(-) (limited to 'drivers/base/firmware_loader/fallback.c') diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c index 9b65837256d6..45cc40933a47 100644 --- a/drivers/base/firmware_loader/fallback.c +++ b/drivers/base/firmware_loader/fallback.c @@ -7,6 +7,7 @@ #include #include #include +#include #include "fallback.h" #include "firmware.h" diff --git a/drivers/base/firmware_loader/fallback.h b/drivers/base/firmware_loader/fallback.h index 550498c7fa4c..ca7e69a8417b 100644 --- a/drivers/base/firmware_loader/fallback.h +++ b/drivers/base/firmware_loader/fallback.h @@ -12,12 +12,14 @@ * * @force_sysfs_fallback: force the sysfs fallback mechanism to be used * as if one had enabled CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y. + * Useful to help debug a CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y + * functionality on a kernel where that config entry has been disabled. * @old_timeout: for internal use * @loading_timeout: the timeout to wait for the fallback mechanism before * giving up, in seconds. */ struct firmware_fallback_config { - const bool force_sysfs_fallback; + unsigned int force_sysfs_fallback; int old_timeout; int loading_timeout; }; diff --git a/drivers/base/firmware_loader/fallback_table.c b/drivers/base/firmware_loader/fallback_table.c index 981419044c7e..92365e053e30 100644 --- a/drivers/base/firmware_loader/fallback_table.c +++ b/drivers/base/firmware_loader/fallback_table.c @@ -19,6 +19,9 @@ /* Module or buit-in */ #ifdef CONFIG_FW_LOADER_USER_HELPER +static unsigned int zero; +static unsigned int one = 1; + struct firmware_fallback_config fw_fallback_config = { .force_sysfs_fallback = IS_ENABLED(CONFIG_FW_LOADER_USER_HELPER_FALLBACK), .loading_timeout = 60, @@ -26,4 +29,18 @@ struct firmware_fallback_config fw_fallback_config = { }; EXPORT_SYMBOL_GPL(fw_fallback_config); +struct ctl_table firmware_config_table[] = { + { + .procname = "force_sysfs_fallback", + .data = &fw_fallback_config.force_sysfs_fallback, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = proc_douintvec_minmax, + .extra1 = &zero, + .extra2 = &one, + }, + { } +}; +EXPORT_SYMBOL_GPL(firmware_config_table); + #endif diff --git a/kernel/sysctl.c b/kernel/sysctl.c index f98f28c12020..bdf7090b106d 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -253,6 +253,10 @@ extern struct ctl_table random_table[]; extern struct ctl_table epoll_table[]; #endif +#ifdef CONFIG_FW_LOADER_USER_HELPER +extern struct ctl_table firmware_config_table[]; +#endif + #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT int sysctl_legacy_va_layout; #endif @@ -748,6 +752,13 @@ static struct ctl_table kern_table[] = { .mode = 0555, .child = usermodehelper_table, }, +#ifdef CONFIG_FW_LOADER_USER_HELPER + { + .procname = "firmware_config", + .mode = 0555, + .child = firmware_config_table, + }, +#endif { .procname = "overflowuid", .data = &overflowuid, -- cgit v1.2.3 From 2cd7a1c6dcd33e7c1a82b254871230f29866d4e9 Mon Sep 17 00:00:00 2001 From: "Luis R. Rodriguez" Date: Sat, 10 Mar 2018 06:14:52 -0800 Subject: firmware: enable to force disable the fallback mechanism at run time You currently need four different kernel builds to test the firmware API fully. By adding a proc knob to force disable the fallback mechanism completely we are able to reduce the amount of kernels you need built to test the firmware API down to two. Acked-by: Kees Cook Signed-off-by: Luis R. Rodriguez Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_loader/fallback.c | 5 +++++ drivers/base/firmware_loader/fallback.h | 4 ++++ drivers/base/firmware_loader/fallback_table.c | 9 +++++++++ 3 files changed, 18 insertions(+) (limited to 'drivers/base/firmware_loader/fallback.c') diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c index 45cc40933a47..d6838e7ec00c 100644 --- a/drivers/base/firmware_loader/fallback.c +++ b/drivers/base/firmware_loader/fallback.c @@ -643,6 +643,11 @@ static bool fw_force_sysfs_fallback(unsigned int opt_flags) static bool fw_run_sysfs_fallback(unsigned int opt_flags) { + if (fw_fallback_config.ignore_sysfs_fallback) { + pr_info_once("Ignoring firmware sysfs fallback due to debugfs knob\n"); + return false; + } + if ((opt_flags & FW_OPT_NOFALLBACK)) return false; diff --git a/drivers/base/firmware_loader/fallback.h b/drivers/base/firmware_loader/fallback.h index ca7e69a8417b..dfebc644ed35 100644 --- a/drivers/base/firmware_loader/fallback.h +++ b/drivers/base/firmware_loader/fallback.h @@ -14,12 +14,16 @@ * as if one had enabled CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y. * Useful to help debug a CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y * functionality on a kernel where that config entry has been disabled. + * @ignore_sysfs_fallback: force to disable the sysfs fallback mechanism. + * This emulates the behaviour as if we had set the kernel + * config CONFIG_FW_LOADER_USER_HELPER=n. * @old_timeout: for internal use * @loading_timeout: the timeout to wait for the fallback mechanism before * giving up, in seconds. */ struct firmware_fallback_config { unsigned int force_sysfs_fallback; + unsigned int ignore_sysfs_fallback; int old_timeout; int loading_timeout; }; diff --git a/drivers/base/firmware_loader/fallback_table.c b/drivers/base/firmware_loader/fallback_table.c index 92365e053e30..7428659d8df9 100644 --- a/drivers/base/firmware_loader/fallback_table.c +++ b/drivers/base/firmware_loader/fallback_table.c @@ -39,6 +39,15 @@ struct ctl_table firmware_config_table[] = { .extra1 = &zero, .extra2 = &one, }, + { + .procname = "ignore_sysfs_fallback", + .data = &fw_fallback_config.ignore_sysfs_fallback, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = proc_douintvec_minmax, + .extra1 = &zero, + .extra2 = &one, + }, { } }; EXPORT_SYMBOL_GPL(firmware_config_table); -- cgit v1.2.3 From 60fa74263cbeae1704908c403aba2bfd62c798e8 Mon Sep 17 00:00:00 2001 From: "Luis R. Rodriguez" Date: Sat, 10 Mar 2018 06:14:55 -0800 Subject: rename: _request_firmware_load() fw_load_sysfs_fallback() This reflects much clearer what is being done. While at it, kdoc'ify it. Signed-off-by: Luis R. Rodriguez Signed-off-by: Greg Kroah-Hartman --- Documentation/driver-api/firmware/fallback-mechanisms.rst | 2 +- drivers/base/firmware_loader/fallback.c | 13 ++++++++++--- 2 files changed, 11 insertions(+), 4 deletions(-) (limited to 'drivers/base/firmware_loader/fallback.c') diff --git a/Documentation/driver-api/firmware/fallback-mechanisms.rst b/Documentation/driver-api/firmware/fallback-mechanisms.rst index 4055ac76b288..f353783ae0be 100644 --- a/Documentation/driver-api/firmware/fallback-mechanisms.rst +++ b/Documentation/driver-api/firmware/fallback-mechanisms.rst @@ -112,7 +112,7 @@ Since a device is created for the sysfs interface to help load firmware as a fallback mechanism userspace can be informed of the addition of the device by relying on kobject uevents. The addition of the device into the device hierarchy means the fallback mechanism for firmware loading has been initiated. -For details of implementation refer to _request_firmware_load(), in particular +For details of implementation refer to fw_load_sysfs_fallback(), in particular on the use of dev_set_uevent_suppress() and kobject_uevent(). The kernel's kobject uevent mechanism is implemented in lib/kobject_uevent.c, diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c index d6838e7ec00c..0a8ec7fec585 100644 --- a/drivers/base/firmware_loader/fallback.c +++ b/drivers/base/firmware_loader/fallback.c @@ -535,8 +535,15 @@ exit: return fw_sysfs; } -/* load a firmware via user helper */ -static int _request_firmware_load(struct fw_sysfs *fw_sysfs, +/** + * fw_load_sysfs_fallback - load a firmware via the syfs fallback mechanism + * @fw_sysfs: firmware syfs information for the firmware to load + * @opt_flags: flags of options, FW_OPT_* + * @timeout: timeout to wait for the load + * + * In charge of constructing a sysfs fallback interface for firmware loading. + **/ +static int fw_load_sysfs_fallback(struct fw_sysfs *fw_sysfs, unsigned int opt_flags, long timeout) { int retval = 0; @@ -621,7 +628,7 @@ static int fw_load_from_user_helper(struct firmware *firmware, } fw_sysfs->fw_priv = firmware->priv; - ret = _request_firmware_load(fw_sysfs, opt_flags, timeout); + ret = fw_load_sysfs_fallback(fw_sysfs, opt_flags, timeout); if (!ret) ret = assign_fw(firmware, device, opt_flags); -- cgit v1.2.3 From ccce305bd411f1c3a15eb8ca3b3cf827e38bd47c Mon Sep 17 00:00:00 2001 From: Stephen Rothwell Date: Wed, 21 Mar 2018 19:06:35 +1100 Subject: firmware: explicitly include vmalloc.h After some other include file changes, fixes: drivers/base/firmware_loader/fallback.c: In function 'map_fw_priv_pages': drivers/base/firmware_loader/fallback.c:232:2: error: implicit declaration of function 'vunmap'; did you mean 'kunmap'? [-Werror=implicit-function-declaration] vunmap(fw_priv->data); ^~~~~~ kunmap drivers/base/firmware_loader/fallback.c:233:18: error: implicit declaration of function 'vmap'; did you mean 'kmap'? [-Werror=implicit-function-declaration] fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0, ^~~~ kmap drivers/base/firmware_loader/fallback.c:233:16: warning: assignment makes pointer from integer without a cast [-Wint-conversion] fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0, ^ drivers/base/firmware_loader/fallback.c: In function 'firmware_loading_store': drivers/base/firmware_loader/fallback.c:274:4: error: implicit declaration of function 'vfree'; did you mean 'kvfree'? [-Werror=implicit-function-declaration] vfree(fw_priv->pages); ^~~~~ kvfree drivers/base/firmware_loader/fallback.c: In function 'fw_realloc_pages': drivers/base/firmware_loader/fallback.c:405:15: error: implicit declaration of function 'vmalloc'; did you mean 'kvmalloc'? [-Werror=implicit-function-declaration] new_pages = vmalloc(new_array_size * sizeof(void *)); ^~~~~~~ kvmalloc drivers/base/firmware_loader/fallback.c:405:13: warning: assignment makes pointer from integer without a cast [-Wint-conversion] new_pages = vmalloc(new_array_size * sizeof(void *)); ^ Signed-off-by: Stephen Rothwell Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_loader/fallback.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/base/firmware_loader/fallback.c') diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c index 0a8ec7fec585..d231bbcb95d7 100644 --- a/drivers/base/firmware_loader/fallback.c +++ b/drivers/base/firmware_loader/fallback.c @@ -8,6 +8,7 @@ #include #include #include +#include #include "fallback.h" #include "firmware.h" -- cgit v1.2.3 From c6263a48459934c9d07153e6d7f0fa43462d8dd2 Mon Sep 17 00:00:00 2001 From: "Luis R. Rodriguez" Date: Wed, 21 Mar 2018 15:34:28 -0700 Subject: firmware: fix typo on pr_info_once() when ignore_sysfs_fallback is used When the sysctl knob is used ignore the fallback mechanism we pr_info_once() to ensure its noted the knob was used. The print incorrectly states its a debugfs knob, its a sysctl knob, so correct this typo. Signed-off-by: Luis R. Rodriguez Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_loader/fallback.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/base/firmware_loader/fallback.c') diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c index d231bbcb95d7..31b5015b59fe 100644 --- a/drivers/base/firmware_loader/fallback.c +++ b/drivers/base/firmware_loader/fallback.c @@ -652,7 +652,7 @@ static bool fw_force_sysfs_fallback(unsigned int opt_flags) static bool fw_run_sysfs_fallback(unsigned int opt_flags) { if (fw_fallback_config.ignore_sysfs_fallback) { - pr_info_once("Ignoring firmware sysfs fallback due to debugfs knob\n"); + pr_info_once("Ignoring firmware sysfs fallback due to sysctl knob\n"); return false; } -- cgit v1.2.3